Transcript Biology 20 - Mr. Lechner`s Biology 20 Wiki

Unit 1 - Introduction
“bios” – life, living things, “logy” – the study of
Biology - the study of life
Major branches of biology:
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Zoology – the study of animals
Botany – the study of plants
Microbiology – the study of microorganisms
Ecology – the study of the interaction of living
organisms with one another and with the nonliving part of their environment
Cytology – the study of cells
Questions 1-3, page 6
1. How are species related the the concept of
biodiversity?
- Biodiversity is the variety and number of species in a
given area
2. How do the characteristics of living things contribute
to an organism’s survival?
- The cells that are the basic unit of life carry out the
functions needed to support and maintain life, for
which they require a continual supply of energy. The
ability to respond to the environment helps an
organism to avoid injury and death, as well as meet
material needs. Reproduction and development
enable species survival.
Questions 3-4, page 6
3. Describe the relationship between cells
and organisms.
- All organisms are made of one or more
cells, which are the functional units of life,
carrying out the activities to support life.
4. How does diversity depend on a species’
ability to reproduce?
- Without the ability to reproduce, a species
would become extinct, which would lead
to a decrease in biodiversity.
Question 5, page 6
5. You respond automatically to many
different stimuli, such as loud noises.
Why might a quick response to a sound
be important?
- A quick response could protect against
hearing damage or a physical threat.
Questions 1-3, page 11
1. Describe a biological system.
- A system is a group of interrelated, interacting
parts that make up a whole.
2. Give an example of how structure is related to
function in living things.
- Structure determines function; the snout beetle’s
feet have prongs and pads to walk on both
smooth and rough surfaces.
3. Why is homeostasis essential for living things?
- It enables organisms to survive in diverse and
changing environments.
Question 4-5, page 11
4. What is the relationship between adaptation
and natural selection?
- Natural selection leads to different adaptations
in different environments
5. How are structure and function related to
adaptation?
- An adaptation is a genetic change that can
affect the structure of some aspect of an
organism’s body and how well it functions in a
given environment.
Questions 6 & 7, page 11
6. How is the process of natural selection
involved in evolution?
- Natural selection of different adaptations in
different environments can lead to new species.
7. Do you think homeostasis is necessary at the
level of the single cell? Explain?
- Stable conditions within a cell are necessary for
the cell’s survival, whether in a unicellular or
multicellular organism. If homeostasis is not
maintained within a cell, cell functions can be
disrupted. In turn, this can disrupt functions at
higher levels of organization.
Questions 1-3, page 17
1. What role do hypothesis play in scientific inquiry?
A hypothesis provides a testable explanation of an
observation.
2. What is the difference between an independent
variable and a dependent variable?
- independent variable is manipulated, a dependent
variable shows the effect of that manipulation.
3. How is the meaning of theory in science different
from the everyday use of the term?
- A scientific theory is widely accepted explanation that
is supported by evidence. In everyday language, a
theory is a guess.
Questions 4-5, page 17
4. How are hypotheses and theories related?
- Hypotheses and theories are both proposed
explanations for a scientific question. Observations
and data collected in testing hypotheses contribute to
the broader question that is addressed by a theory. A
theory, in turn, provides the framework for new
hypotheses.
5. Give examples of different ways in which observations
are used in scientific inquiry.
- Scientific questions are developed from intial
observations. Observations are also made to test
hypotheses.
Question 6, page 17
6. Why is the statement “All life is made of
cells” an example of a theory? Explain.
- When first proposed, the idea that all life is
made of cells changed the way scientists
thought about what defines an organism.
Not only did it encompass all
accumulated evidence, but it also
provided the framework for new
investigations.
Questions 1-3, page 23
1. How do light microscopes differ from electron
microscopes?
- Light microscopes use light to view specimens , including
living specimens. Electron microscopes use electrons
to view specimens at higher magnifications but cannot
examine living specimens.
2. Why is computer modeling used in biological studies?
- To model anything that is not practical or ethical to do
in the real world.
3. How does molecular genetics add to our understanding
of genes?
- Molecular genetics is the study of inheritance on a
molecular level. DNA is the molecule that encodes
genetic information. A gene is a segment of DNA.
Questions 4-5
4. Viruses are smaller than cells. What types of
microscopes could be used to study them?
Explain.
- Light microscopes are not powerful enough to
clearly view viruses, so electron microscopes
would need to be used.
5. Provide an example of how technology has
helped biologists gain a better understanding of
life.
- Answers could include imaging technologies show
more details of cells, computer analysis of genes
and genomes, and computer models
Question 6
6. Genomics can be used to study the
genetic relationships among species.
Why might genomics be important for
evolution research?
- By comparing the genomes of different
species, scientists can establish how
closely related species are finding
occurrences of shared DNA sequences
and genes.
Questions 1-3, page 27
1. Give three examples of ways in which biology can
help inform everyday decisions.
- Knowledge of biology can inform decisions about
diet, using sunscreen, and exercise.
2. What are some of the potential benefits and risks of
biotechnology?
- Benefits: treatment and prevention of disease and
illness, improving crop growth.
- Risks: ethical concerns, privacy, potential negative
health and environmental effects
3. What are some of the unanswered questions in
biology?
- Life on other planets, cancer cure, viruses, memory
Questions 4-5
4. Scientists disagree on whether genetically modified foods
are safe to eat. What type of scientific evidence would be
needed to show that a genetically modified food is
unsafe?
- Ex: long-term feeding trials comparing health of animals
that do and don’t eat GM foods. The best evidence
will be collected over time with humans. Over several
years, there will be more data about the health of
people who eat GM foods compared with people who
do not.
5. How might your study of biology help inform you about
your lifestyle choices?
- A knowledge of biology helps you make informed
decisions about lifestyle choices that could affect your
health and quality of life and health of the environment.
Question 6
6. What effects might genetically modified
plants and animals have on an
ecosystem if they breed with wild plants
and animals?
- They could decrease biodiversity and affect an
ecosystem in unpredictable ways.